1) Field of the Invention
The present invention relates to an ink supplying apparatus for use in a printing press such as a rotary press or a sheet-fed printing press, and more particularly to an ink supplying apparatus equipped with an ink tray attachable/detachable to an ink fountain.
2) Description of the Related Art
As FIGS. 16 and 17 show, a printing press such as a rotary press or a sheet-fed printing press is provided with an ink supplying apparatus 100 in which an ink fountain 102 is placed in front of an ink fountain roller 101. The ink fountain 102 is composed of a circumferential surface of the ink fountain roller 101, a plurality of ink keys (blades) 103 constituting a bottom section of the ink fountain 102, and two side plates 104 (only one on the interior side is shown in FIG. 16) provided at both side surfaces of each of the ink keys 103 so that their front edges come into contact with the circumferential surface of the ink fountain roller 101 to slide thereon. In this construction, an ink lying within the ink fountain 102 is supplied through a gap between the ink fountain roller 101 and the tip portion of each of the ink keys 103 to the ink fountain roller 101 and then transferred through a non-shown ink ductor roller to a group of ink rollers lying on the downstream side.
The plurality of ink keys 103 are, as shown in FIG. 17, arranged in parallel with each other in a lateral direction of the apparatus so that the ink keys 103, 103 adjacent to each other are brought into contact with each other while both the end ink keys 103 and the side plates 104 are brought into contact with each other. In addition, the ink keys 103 are made to be driven independently of each other to rock or swing about a supporting shaft 105, and an ink quantity control device 106 is situated under the respective ink keys 103.
The ink quantity control device 106 is provided with an adjusting cam 106b engaging with a lower surface of the tip portion of each of the ink keys 103 and a pusher 106a brought into contact with the adjusting cam 106b to rock the adjusting cam 106b by its telescopic motion, namely, protruding/retracting movements. Additionally, the tip portion of each of the ink keys 103 is driven to rock in a manner that the pusher 106a is operated appropriately to protrude/retract for rocking the adjusting cam 106b so that its engaging portion of the adjusting cam 106b with the ink key 103 lifts/lowers, thereby controlling the gap between the ink key 103 and the ink fountain roller 101 to adjust the thickness of the ink film to be supplied.
Meanwhile, in the aforesaid conventional ink supplying apparatus 100, a microscopic gap is secured between the adjacent ink keys 103, 103 and between both the end ink keys 103 and the side plates 104 in order to permit the mutual sliding motion. Accordingly, there is a possibility that the ink permeates through the very small gap, for example, between the ink keys 103, 103 by the capillary phenomenon or the like. If the ink is hardened after permeating through the gap between the ink keys 103, 103, the operation of the ink keys 103 becomes unstable and the worst case reaches the difficulty of movement thereof, so that a problem exists in that the high-accuracy control of the ink film becomes impossible.
In addition, after the completion of printing or in the ink replacement, although there is a need to clean the interior of the ink fountain 102 by wiping off the ink remaining in the interior of the ink fountain 102 with a waste or the like, or by washing it off with a cleaning solvent, the removal of the ink is difficult because the ink shows a high viscosity. Particularly, difficulty is experienced in removing the ink permeating into the gap between the ink keys 103, 103 so that a severe burden falls on the cleaning worker. Still additionally, although, for improving the productivity, there is a need to shorten the preparation for the order change for enhancing the availability factor of the apparatus, if the load on the cleaning in the ink replacement is severe as mentioned above, the cleaning takes time largely. For this reason, it has been desired strongly to relieve the burden to be imposed on the worker through the labor-saving in the cleaning operation and further to enhance the availability factor of the apparatus through the shortening of the cleaning time.
The present invention has been developed in consideration of the above-mentioned problems, and it is therefore an object of the invention to provide an ink supplying apparatus which is capable of achieving the labor-saving of the cleaning operation and the shortening of the working time in ink replacement or the like of a printing press.
For this purpose, an ink supplying apparatus according to this invention involves the following features.
That is, an ink supplying apparatus according to this invention is equipped with an ink fountain roller, left- and right-hand side plates brought into sliding contact with a circumferential surface of the ink fountain roller to constitute a side wall section of an ink fountain, a plurality of ink keys arranged in parallel with each other to constitute a bottom section of the ink fountain and a supporting base for supporting the side plates and the plurality of ink keys, the ink supporting apparatus is characterized by comprising an ink tray having a bottom plate placed in the interior of the ink fountain for covering upper surfaces of the ink keys and a deflection restraining structure for supporting the bottom plate from below to restrain a deflection or bending of the ink tray.
In this way, since the ink tray covering the upper surfaces of the ink keys is provided in the interior of the ink fountain, the contact area of the ink keys with the ink is reducible considerably to reduce the possibility of the permeation of the ink into the gap between the ink keys, thereby stabilizing the operations of the ink keys and shortening the cleaning time of the interior of the ink fountain to improve the productivity. In addition, at the mounting of the ink tray in the ink fountain, since the deflection restraining structure supports the bottom plate from below to limit the deflection thereof, the weight reduction of the ink tray becomes feasible to provide easy handling of the ink tray, thus further improving the productivity.
Preferably, the aforesaid deflection restraining structure is made up of a supporting member protruding downwardly from a bottom surface of the bottom plate and a through hole made from an upper surface of the ink key to a bottom surface thereof so that, when the ink tray is mounted in the ink fountain, a lower end portion of the supporting member is brought into contact with the supporting base in a state of passing through the through hole to support the bottom plate.
With this construction, the deflection restraining structure can support the bottom plate from below without interfering with the ink key.
Alternatively, the deflection restraining structure is made up of a supporting member protruding upwardly from the supporting base and a through hole made to a location of the supporting member to extend from an upper surface of the ink key to a bottom surface thereof so that, when the ink tray is mounted in the ink fountain, a tip portion of the supporting member projecting through the through hole onto an upper surface of the ink key is brought into contact with the bottom plate of the ink tray to support the bottom plate.
Also with this construction, the deflection restraining structure can support the bottom plate from below without interfering with the ink key. Additionally, because the supporting member is installed on the supporting base without being required to be placed on each of ink trays, the increase in cost is suppressible.
Preferably, the supporting member is made to be attachable/detachable to/from the supporting base. This facilitates the replacement of the supporting member and permits the cleaning in a state removed.
Still alternatively, the aforesaid deflection restraining structure is made up of a first supporting member protruding downwardly from the bottom surface of the bottom plate, a second supporting member protruding upwardly from the supporting base in connection with the first supporting member and a though hole made to the location of the second supporting member to extend from a surface of the ink key to the bottom surface so that, when the ink tray is mounted in the ink fountain, a lower end portion of the first supporting member is brought into contact with a tip portion of the second supporting member to support the bottom plate.
Similarly, with this construction, the deflection restraining structure can support the bottom plate from below without interfering with the ink key. Additionally, owing to shortening the each of the supporting members, the possibility of bending thereof is reducible at handling.
Preferably, the lower end portion of the first supporting member and the tip portion of the second supporting member are brought into contact with each other in the interior of the through hole. This eliminates the troubles in the cleaning of the surface of the ink key because the second supporting member does not appear from the surface of the ink key at the removal of the ink tray.
Furthermore, in each of the aforesaid constructions, it is also possible that the supporting member is located to support the bottom plate at a central portion of the ink tray in its cross (width) direction. Accordingly, the supporting member supports the cross-direction central portion of the ink tray showing the largest deflection, thus restraining the deflection thereof with high efficiency.
Still furthermore, it is also acceptable that a plurality of supporting members are provided in a cross direction of the apparatus. This supports the bottom plate of the ink tray in the apparatus cross direction through the use of the plurality of supporting members, thus restraining the deflection with higher efficiency.
Yet furthermore, it is also acceptable that the through hole has an elongated slit-like configuration extending in a longitudinal (forward and backward) direction of the ink key. In this case, the interference between the supporting member and the ink key is preventable.
Moreover, it is also possible that the through hole is made between the ink keys adjacent to each other.